Lagomarsino



Sept. 24, 1963 E. LAGOMARSINO 3,104,812

CALCULATING MACHINE ADAPTED TO PERFORM DIVISIONS Filed Oct. 5, 1960 12 Sheets-Sheet l EMILIO LAGOMARSINO INVENTOR.

AGENL Sept. 24, 1963 E. 'LAGOMARSINO CALCULATING MACHINE ADAPTED TO PERFORM DIVISIONS Filed Oct. 5, 1960 12 Sheets-Sheet 2 EMILIO LAGOMARSINO INVENTOR.

Sept. 24, 1963 E. LAGOMARSINO CALCULATING MACHINE ADAP'IED TO PERFORM DIVISIONS Filed Oct. 3, 1960 I 12 Sheets-Sheet 3 INVENTOR.

AGENT.

Sept. 24, 1963 E. LAGOMARSINO 3,104,812

CALCULATING MACHINE ADAPTED TO PERFORM DIVISIONS 12 Sheets-Sheet 4 Filed Oct. 5. 1960 INVENTOR: EMILIO LAGOMARSINO Sept. 24, 1963 E. LAGOMARSINO CALCULATING MACHINE ADAPTED TO PERFORM DIVISIONS Filed Oct- 5, 1960 l2 Sheets-Sheet 5 Sept. 24, 1963 E. LAGOMARSINO CALCULATING MACHINE ADAPTED TO PERFORM DIVISIONS Filed Oct. 5. 1960 12 Sheets-Sheet 6 EMILIO LAGOMARSINO INVENTOR.

i AGENI Sept. 24, 1963 E. LAGOMARSINO 3,104,812

CALCULATING MACHINE ADAPTED TO PERFORM DIVISIONS Filed Oct. 5, 1960 12 Sheets-Sheet 7 3; 5 3 U LI 0 T I EMILIO LAGOMARSINO INVENTOR.

BY g p AGENT.

Sept. 24, 1963 E. LAGOMARSINO 3,104,812

CALCULATING MACHINE ADAPTED TO PERFORM DIVISIONS Filed 001;. 5, 1960 12 Sheets-Sheet 8 EMILIO LAGOMARSINO INVENTOR.

AGENT,

Sept. 24, 1963 E. LAGOMARSINO CALCULATING MACHINE ADAPTED TO PERFORM DIVISIONS Filed Oct. 5, 1960 12 Sheets-Sheet 9 EMILIO LAGOMARSINO INVENTOR.

1 9 o AQENT Sept. 24, 1963 E. LAGOMAR'SINO 3,104,812

CALCULATING MACHINE ADAPTED 'ro PERFORM DIVISIONS Filed OCB. 3, 1960 12 Sheets-Sheet 1O TO RESTORING 1Z1 MECHANISM EMILIO LAGOMARSINO INVENTOR.

AGEN'E Sept. 24, 1963 E. LAGOMARSINO CALCULATING MACHINE ADAPTED TO PERFORM DIVISIONS Filed 001;. 3, 1960 1? Sheets-Sheet 11 EMILIO LAGOMARS|NO INVENTOR.

AGENI Sept. 24, 1963 E. LAGOMARSINO CALCULATING MACHINE ADAPTED TO PERFORM DIVISIONS Filed Oct. 3, 1960 12 Sheets-Sheet 12 EMILIO LAGOMARSINO INVENTOR.

AGENT.

United States Patent Italy Filed Oct. 3, 1960, Ser. No. 60,027 Ciaims priority, application Italy Apr. 12, 196d 18 Claims. (Cl. 235-43) The present invention relates to a calculating machine, preferably of the type wherein the result of a mathematical operation is printed on a tape, having means for the performance of divisions as well as other operations such as addition, subtraction and multiplication.

It is known toperform divisions on an automatic calculator by successively subtracting the value of the divisor from that of the dividend which has been stored in a totalizer; the number of such subtractions, determined by a suitable counter, represents the quotient of the division whereas the final dilterence stored in the totalizer (generally of a value lower than that of the divisor) is printed or otherwise indicated as the remainder.

In a conventional calculator of this type, to which the present invention is particularly applicable, the tot-ah izer causes the sense of the operation to be reversed (i.e. changed from subtractive to additive) as soon as its capacity is exceeded, i.e. whenever the subtrahend is larger than the stored minuend so the the calculated difference would be of negative sign. The ensuing additive cycle restores the positive balance existing immediately prior to the final subtraction step; at the same time the movable register for the storage of the divisor, such as the usual pin carriage, is displaced by one step so as to shift the divisor by one digital column toward the right with respect to the dividend. The same sequence of operations is then repeated until the final position is reached in which the rightmost digit of the divisor is operatively aligned with the units column of the dividend; after the final arithmetical operation in that position, the machine stops and displays the quotient as well as the remainder, if any.

The number of cycles performed by the calculator in each position of alignment exceeds thus by two the numer of legitimate subtractions, this excess creating difficulties in the control of the printer or other display mechanism which must give the true number of such subtractions. It should be noted that the same two supernurnerary cycles occur also if the vallue stored in the totalizer after a succession of subtractions is exactly zero; in such case the machine will perform one further subtraction, in order to exceed the capacity of the totalizer and to give rise to the signal of a reversal of operations, and one further addition to restore the totalizer to zero.

Anim-portant object of my present invention is the provision of improved and simplified means for suppressing the extra cycles in the control of the quotient indicator.

Another object of this invention is to provide means selectively operable to toreshorten a division operation by halting the step-by-step return of the control carriage in a position in which the units digit of the divisor is operatively aligned with a column other than the units column of the dividend, the machine then indicating in mathematically correct tashi'ona quotient along with a remainder which is larger than the divisor. This abbreviated mode of division will be advantageous particularly in those cases where only the highest decade or decades of the quotient are of interest.

ice

A further object of the instant invention is the provision of means to accelerate the display of the quotient in all those casest inwhich the dividend has one or more terminal zeros and the division is performed without remainder, i.e. whenever the register is at zero prior to the return of the control carriage to its units position.

In accordance with a principal feature of the invention I provide, in a calculating machine of the general character outlined above, a lost-motion connection between a counting wheel and a driving member therefor which is advanced by a predetermined number of steps (preferably a single step), under the control of the totalizer, in response to each calculating cycle irrespective of sign. The lost-motion connection, which may be in the form of a pin-and-slot coupling between two disks on the shaft of the counting wheel, is so arranged that the counting wheel is not stepped until the third operating cycle of each carriage position; this compensates for the two supernumerary cycles at the end of each counting sequence. As the carriage is shifted by one column under the contnol of a back-spacing mechanism known per se, a restoring device such as a spring re-establishes the initial position of the lost-motion connection so that the same two-step lag occurs in the following sequence of cycles. In a preferred embodiment, the re-establishment of the initial position is effected by a resilient force which, in the first two cycles of the next operating sequence, is overcome by the driving member while the counting wheel is held in position by a yield-able indexing device.

In accordance with another feature of the invention there is provided, in combination with the aforementioned back-spacing mechanism, a linkage controlled by the totalizer for converting the operation of that mechanism in an off-normal carriage position into a sequence of endof-divisicn steps similar to those normally performed when the back spacer is actuated in the units position of the carriage. This mode of operation can be brought about in either of two ways, i.e. either manually with the aid of a suitable selector (such as the conventional correction key of the machine) or automatically if the totalizer is in zero position at the end of a columnar sequence of calculating cycles. For this purpose I advantageously use a link which is normally displaced at the end of the division by a slidable support for the counting Wheel, serving to align the latter successively with the respective digital quotient pinions, in the terminal position of the support; such displacement interposes an operating memher for the initiation of the end-of division sequence in the path of a reciprocal element periodically displaced by the back-spacing mechanism. As this mechanism, operates in response to the two supernumerary cycles which drive the totalizer first negative and then again positive or to zero, a special sign indicator controlled by the totalizer renders the reciprocation of the element ineflective if the totalizer shows a positive balance at the end of the second cycle; it, however, that balance is Zero, the sign indicator causes the second reciprocation to be communicated to the operating member for the end-ofdivision sequence whereby the quotient so far computed will be printed immediately along with the necessary number of zeros as determined .by the number of steps which the carriage and the counting-wheel support, both suitably interconnected, had yet to take to return to normal. Furthermore, a depression of the correction key acts in similar manner to establish a link between the reciprocating element and the end-of-division operator to fioreshorten the calculation and to cause a printing of the incompletely determined quotient along with the correot remainder.

The above and other objects, features and advantages of my invention will become more fully apparent from 3 V the following detailed description of a preferred embodiment, reference being made to the accompanying drawing in which: a

FIG. 1 is a fragmentary perspective view of a set of sector-shaped digital gears and associated elements including a counting-wheel'support;

FIG. 2'is a' perspective view of a linkage between one of the sector gears of FIG. 1 and a stop mechanism for the counting-wheel support;

FIG-3 is a view similar to FIG. 1 but showing an assembly of quotient pinions adapted to co-operate with the counting wheel; V FIG. 4 is another fragmentary perspective view showing details of the lost-motion coupling for the drive of the counting wheel; a

FIG. 5 is a side-elevational view of the assembly of FIG. 4, drawn to a larger scale;

FIGS. 6' and 6A are side-elevational views of part of the coupling of FIGS. 4'and 5, shown in two difierent positions of operation; a

FIG. 7 is a perspective illustration of a linkage for interconnecting the counting-Wheel support with the movable carriage of the machine;

FIG. 8 is a similar view of another part of the same linkage;

FIG. 9 is a sectional elevation taken substantially on line IXIX of FIG. 1 but showing some of the pants illustrated in FIG. 8;

FIG. 10 is a further perspective view illustrating details of the mechanism for rendering effective the link age of 'FIGS. 79;

FIG. 11 is a perspective view of an assembly serving to fore'shorten the calculation of the machine;

FIGLllA is a detail view, in elevation on line XIA- XIA of FIG. 11, of part of the assembly shown there;

the printing of the result o f'the previous operation on the tape 103, whereupon the dividend is registered by means of the keys 1115 and is transferred to the totalizer through actuation of the dividend key 106. 7 Alternatively, the

repeat key 108 may be operated to re-enter a total obtain-ed in a preceding operation, such total being then again stored in the totalizer in the usual manner. It should be noted that the two keys 106 and 10 8 are equivalent for purposes of the present invention in that the depression of either of them initiates the same sequence of operations.

When the dividend has been stored with the aid of key 1116 or 108', the divisor is registered by means of the same keys 105, whereupon the divisor key 1117 is depressed.

FIG. 12- is a similar perspective view illustrating a relatedassembly which serves to accelerate the end of division with zero remainder; I

FIGS. 13, 14 and 15 are elevational views of part of the assembly of FIG. 12 in three different stages of operation;

FIG. 16 is a s'ide-elevational view taken substantially on the line XVIXVI of FIG. 3 FIG; 17 is a perspective rear view of part of the system shown in FIGS. 8-40;

.- shown in FIGS. 121. a

Reference will first be made to FIG.' 22 for a description of the overall features of a machine to which my invention is applicable. V

The machine shown in FIG. 22 comprises avhousing 1110 pnovided at its front with the usual keyboard 10:1 and having at its rear a holder 102. fora roll of tape 103 on which the results of the performed'calculations are printed by conventional type bars 104% The keyboard 101 comprises the usual numerical keys 1115 (including a key f or the digit 0), a dividend key 1416, a divisor key 107, a repeat key 1118, a correction key 109 and a variety of other keys which pertain to mathemati- "cal operations other than Qdivisions, being therefore of no further interest in connection with the present invention. a 1

The machine, having printed both the dividend and the divisor on the tape 1103, then operates automatically to compute the quotient and the remainder, if any, which are alsorecorded with'distinctive marks on the tape.

Themode of *operationof the machine in the performance of these tasks will now be described in details with reference to FIGS. 1-21, it being understood that such conventional elements as the usual driving motor, the totalizer proper, as well as various shafts, linkages, restoring springs and similar elements have been omitted (except Where necessary for an understanding of the in vention) in order to simplify the disclosure.

FIG. 1 illustrates a set of digital sector gears 1 which are rotatably mounted on a common shaft (not shown) in alignment with a similar set of quotient pinions 5, the latter being juxtaposed for independent rotation on a shaft 6 with interposition of suitable spacers not shown. The shaft 6 is lodged in the arms 2, 2 of a swingable yoke which are interconnected by a bar 4, the pivotal axle of the yoke being shown at 3.

A rod 14 extends parallel to shaft 3, to the rear of the latter, and serves as a sliding rail for a generally U- shaped support'9. This support has a rigid extension 11,

i of inverted-U shape, which is guided on a square shaft 13 with the aid of suitable bushings 12. The bushings 1 2 flank a four-pointed counting 'wheel 13 which, like the bushings, has a square internal profile mating with that of the shaft 13. A rack' is is rigid with the support 9 and extends laterally to the left thereof. The entire assembly shown in FIG. 1 is mounted in the rear part of the housing 101 of FIG. 22, thus in the vicinity of the tape printer 104, with the shafts 3, 6, 13 and 14 extending in transverse direction.

Shaft 6 projects leftward beyond arm 2' and engages an eye in a swingable arm 15 whose pivot has been indicated schematically at 15. A link 16, urged clockwise about its pivot 16" by a spring 17 (FIG. 3), is displaceable under the control of a cam 110 which acts through a swingable crank member 120 having a fulcrum at 111'.

" The arm 15 can thus be swung by means of its pin 15",

received in a'camming slot 16 of link 16, between its.

solid-line position, in which the pinions 5' are maintained out of contact with the sector gears 1, and an alternate position shown in dotted lines in which the pinions mesh withthe sector gears. It will be understood that the cam 116 and the member 120 are so controlled that no meshing will occur between the toothed elements 1 and 5 for the'duration of the calculating operations described here- :its bottom with a comb shaped plate 112 having its interstices traversed by'the pinions 5 and associated re-. taining springs 113. The springs 113 act upon the teeth of the pinions with light pressure so" as not unduly to impedethe rotation thereof. One of the teeth of each pinion is somewhat enlarged, as shown at 5', to be blocked gear 1, in a manner known per se, when the quotient stored in the pinion assembly is transferred to the type bars 164 (FIG. 22) via these sector gears.

In the initial stage of operation, if the selector keys 1115 (FIG. 22) are actuated to register the value of a dividend, such value is initially stored on a pin carriage 3 9- shown in FIGS. 7 and 21. From there the dividend is transferred, by conventional means not further illustrated, to a totalizer (not shown) located in a box at the bottom of the machine housing 1%; this transfer takes place under the control of the dividend key 1 and through the intermediary of the sector gears 1. In this particular embodiment there are shown thirteen such sector gears of which all but the first and the last one are provided with individual links 114 articulated to respective levers 18. Each of these levers has an upstanding arm 19 engaged by an associated stop bar. These bars have been designated by the numeral Zii, except for the last one on the extreme right which bears the numeral 2h; see particularly FIGS. 2, 18, 19 and 20. At 2912 the bars are provided with a notch adapted to be engaged by a slotted bottom plate 22 which forms part of a frame 21 supported on a transverse shaft 29. The bars have slotted upper extremities 23a through which the shaft 29 passes with clearance enabling a generally downward displacement thereof from the position illustrated in FIG. 19; the bars are continuously urged into this position by respective springs 24 anchored to the frame 21. The lower extremity 23 of each bar forms a hook which in the position of FIG. 19 is overlain by a ledge 19 of arm 19. Moreover, each of the bars 243 is formed at the top with a lug 23b which over-lies the extremity 23a of the adjacent bar on its right so as to interconnect all the bars in cascade whereby a lowering of any bar 20 will simultaneously lower all the bars positioned to the right thereof. Bar 29, being on the extreme right, lacks the lug 23b but is otherwise identical with the bars 2t). FIG. 19 also shows a guide comb 22' for the bars.

A swingable bridge 25, pivoted on the shaft 29, overlies all the stop bars 251' and 211' to keep them normally depressed against the action of springs 24 whereby, as illustrated in FIG. 19, the notches 26a thereof are maintained disengaged from the slotted plate 22. In this position the levers 18, 19 are free to oscillate under the con trol of their respective sector gears 1 without entraining any of their associated stop bars. If, however, bridge 25 is lifted off the bars by a counter-clockwise rotation about shaft 29, a reciprocation of the arm 19 in first a counterclockwise and then a clockwise sense will move the ledge 19' away from lug 23, thereby allowing the latter to rise, and will then cause the entire bar to be drawn downwardly, as indicated by the arrow 115 in FIG. 19, by reason of the interlinking of ledge 11? with lug 23. Such a reciprocation of arm 19 occurs whenever the sector gears 1 are restored to normal during thetransfer of the dividend to the totalize r. As a result, a stop bar 25 or 29 will be lowered for each significant digit of the dividend and, owing to the cascaded arrangement illustrated in PEG. 20, also for any zero digit to the right of a significant digit. The bars so loweredare held in their new position by the engagement of plate 22' with the notches 20a thereof, this being the position illustrated for bars 26 and 2a" in FIG. 2.

Since the sector gears 1 intervene during every transfer of a dividend, whether the same be a new number or a previously registered total, the aforedescribed sequence of operations will be initiated by the actuation of either key 1% or key 1418. Each of these keys is adapted to displace rearwardly' a lever 116, as indicated by arrow 117 in FIG. 2, whereby a counter-clockwise rotation is imparted to a crank 23 through the intermediary of a member 116 pivoted to lever 116 and a resilient link 118.

Member 116 has a pin 116" which plays in a slot of a bar 118, forming part of the link 118, and is under pressure from a spring 118" also forming part of that link. Crank 28 interposes itself between a continuously rotating cam 28 and a hook 27, attached to a yoke 26, which normally engages a stationary fork 119 (see also FIG. 18) but is now lifted out of it by the crank 28 which bears upon an apron 27' thereof under the properly timed pressure from the cam 28' upon a pin 28" on crank 28. Yoke 26, swingable about shaft 29, has a bifurcate extremity 3t) which within frame 21 engages a pin 25 of bridge 25; thus the assembly 25, 26 is now able to swing counterclockwise on shaft 29, eg under the urging of springs 24,. to an extent suflicient to hold the hook 27 withdrawn from fork 119 and to allow the subsequent entrainment of one or more stop bars .20, 20 by the corresponding arms 19. Assembly 25, 26 remains in this released condition until, upon the completion of the subsequent calculating steps, the crank 12% (FIG. 18) is interposed via a resilient linkage 121, 122 between the aforementioned cam 11d (of. FIG. 3) and an extension 26 of yoke 26 whereby the latter, along with bridge 25, is rotated clockwise to re-engage the book 27 with fork 119 as the team 11d bears upon the stud 12d of crank 120.

The earns 28 and 116 may be keyed to a common shaft, indicated at 111 in FIG. 3, along with other cams whose functions will be described hereinafter.

The first calculating cycle of the machine, i.e. the transfer of the dividend digits to the totalizer, has also cleared the carriage 39 during the return stroke of the affected sector gears 1 whereby the carriage becomes available for the registration of the divisor. Since such carriages are well known, its operation will be described but briefly. It comprises a plurality of digital columns of numerical pins, such as those shown at 123 (0) and 123' (1) in FIG. 21, which can be selectively raised by the actuation of the corresponding keys (FIG. 22); the number of columns, here twelve, corresponds to the maximum number of digits in a divisor. The zero pins 123 also control the displacement of the carriage toward the left relative to a fixed stop not shown; they are, therefore, settable not only by the zero lever 124 but also by a control rod 125 which serves for the initial leftward displacement of the carriage 39 into an extreme digital position from which it is subsequently recalled, column by column, after each additive cycle which terminates each sequence of calculating operations by the totalizer. This final additive cycle occurs whenever the capacity of the totalizer has been exceeded by a subtraction step in which the amount remaining stored in the totalizer was less than the value of the divisor as weighted by the digital position of the carriage, i.e. as multiplied by a factor of 10 where n is the number of steps by which the carriage is displaced from its units position; thus, as the carriage is returned from a higher-ranking denominational order to. the nextlower-ranking one, the value of the weighted divisor is reduced to one tenth of its previous magnitude. When the units position is reached, the divisor as registered on the carriage has assumed its true value and any balance left in the totalizer must be discharged therefrom as a remainder, to be recorded as such by the type bars 164 on the tape 1% (FIG. 22).

The pin carriage 39 is being continuously urged toward the left with reference to the position of a user and as viewed in FIG. 7, by a spring 40 acting through the intermediary of a lever 41 pivoted at 41. A bar 42 connects the lever 41 with a gear sector 43, pivoted at 43', which meshes with a complementary gear sector 44' having a curved extension 44 articulated onto a linkage consisting of a pair of short arms 44", 47 hinged together at 57. The eccentric pivot stud 45 with hexagonal head facilitates the relative meshing of the two gear sectors 43, 44' which are biased, by spring 49 as well as a supplemental spring 126 anchored to a pin 126 on sector 44', in the direction indicated by the arrows whereby a slider 48, fastened to arm 47, is urged toward the left along its supporting shafts 49 and 50 which extend parallel to shaft 14 (of. FIG. 9)- to the rear of the latter. The leftward movement of slider 48 is limited by the carriage 39 with which it is positively coupled and whose locator pins 123 (FIG. 21) are normally in line with the aforementioned fixed stop. Shaft 49, as seen in FIGS. 8-l0 and 17, also supports a pair of interlinked yokes 51, 53.which are interconnected (as described below) so as to be jointly swingable on the shaft but axially fixed thereon. Slider 48, which is similarly swingable, is internally provided with a bracket 48 to which the arm 47 is secured and which does not partake of the angular oscillations of the slider 48 since it is freely rotatable on the shaft 49 between slider portions 48a, 48b. Shaft 50, which spans the arms of yoke 51, is urged forwardly by a spring 128 coiled around a further shaft 127 within a bracket 52; this spring engages the bifurcate left-hand end 53 of yoke 53 which straddles a pin 51 on the right hand arm of yoke 51. Normally, however, any counter-clockwise rotation of the assembly 51, 53 is prevented by a spring 1129 anchored to the right-hand arm of yoke 53'. In such normal position, i.e. before the divisor key 107 is depressed, a lug 56 swingable on shaft 14 (FIGS. 4, and 17) engages the counting-wheel support 9 by means of its hook 56 to define a starting position for this support.

The slider 48, whose movement across the width of the machine is proportional but not necessarilyequal to that of carriage 3-9, has a forwardly protruding dog 57 which is aligned with one of the gaps of rack 10 (FIG. 17) in each stop position of the carriage.

The yoke 53 carries two hooked levers 54, 55 which are normally ineffectual, being held out of contact with other parts of the mechanism by a pin 58 on an arm 58 which is rigid with shaft 49 on the right-hand end thereof. The left-hand end of this shaft carries a link 130 which is caused to swing counter-clockwise, as indicated by arrow 131, upon the actuation of key 107. This action lifts the pin 58" off the levers '54, 5-5 and places the hooked end 64 of the former in the path of the manner already set forth. As the weighted divisor (as heretofore defined) is repetitively subtracted from the amount stored in the totalizer, this amount progressively diminishes and ultimately assumes a negative value. When this occurs, a sign indicator 138 (FIG. 12) swings clockwise, under the control of a bifurcate arm 139 responsive to the position of the totalizer, to initiate a series of operations including the switching of the calculating mechanism from a subtrac to an adding position. If the resulting addition of the weighted divisor completely discharges the totalizer to give a zero reading, indicator 138 remains in its displaced position; if the totalizer is restored'to positive capacity, this indicator returns to its original position. a

A rod 65', elastically linked with a lever 65 through a spring 141), is periodically reciprocated'by, a cam (not shown) and tends to swing lever 65 counter-clockwise but cannot do so as long as the upturned end 138 of indicator 138 opposes the displacement of a member 72 linked with the lever. When the indicator 138 has been swung out of the way of member 72 upon areversal in the sign of a lug 72 on the totalizer charge, the next reciprocation of rod 65 displaces the lever 65 to remove an obstruction from the path of another camoperated member or escapement device, not shown, which in the next cycle returns the carriage 39 by one step to the right in the manner of conventional back-spacing a pin @132 (FIG. 10') carried on a bell crank 63 which is fulcrumed on the stationary wall plate 163. .-An arm 58 (FIG. 10), depending from the pin 58", is raised by this operation to remove a pin 133 from above a finger 134 which is articulated to a lever 59 swingable about an axis 59; simultaneously, arm 61 elevates a a hook 60 into engagement with a cross-piece 59" on lever 59, hook 450 being articulated to a cam-follower member 61 which is periodically acted upon by a cam 62. Cross-piece 59 is also engaged by a bar 63 which is coupled, as shown in FIG. 21, with the control lever 125 for the escapement of the carriage 3 9.

Bell crank 63' is periodically oscillated by a further cam 135. Upon the rise of lever 54 its hook 64 becomes entrained bythe pin 13 2, as the bell crank swings clockwise, this motion imparting a counter-clockwise rotation to the assembly 51, 5-3 which is subsequently held in its rotated position by the hook of lever 55 engaging pin 581. Ann 59 is drawn clockwise by the hook 60 and is arrested in its rearward position by the engagement of a fixed pin 136 by its finger 134. Bar 63 is pulled rearwardly by the swing of arm 58 from which it is subsequently released by a pin 135' on the cam 135; thus this rod is displaced only once. a

The aforedescribed rotation of assembly 51, 53 has also caused a clockwise swing of lug 56 on its shaft 14,

owing to its connection with yoke 51 through apin 137 (see FIGS. 10 and 17 this movement frees the slidable support 9 which at the same time becomes coupled with slider 48 through an engagement of its dog 57 with the rack 10. It will be understood that theposition of slider 48 is at this instant determined by that of the carriage 39 which in turn depends on the number of digits in the divisor registered thereon. Immediately thereafter, the displacement of rod 63 bythe armi59 exerts pressure, via pivotally .displaceable link 63", upon the right-hand end of lever 125 (FIG. 21) whereby a is rigid on a'shaft 142. The resulting rightward dis placement of this shaft causes a similar displacement, parallel to itself, of an actuating rod 66 which is reciprocated by the lever 65 (FIG. 12) whenever the latter swings to initiate the aforedescribed operation of the back-spacing mechanism. Normally, rod 66 is disaligned from a lug 77 on a crank 77 which is fixed to a shaft 143 and has articulated to it two levers88 and 97. Shaft 143 extends across the machine housing in the vicinity of shaftg142 and at its opposite end carries an arm 144 linked to a rod 145. When the rod 66 has been shifted to the right by means of shaft 142, as indicated by the arrows 146 and 147, its next reciprocation brings it into contact with lug 77 and causes the assembly 77, 143, 144 to swing counter-clockwise, against the force of a spring' 148, whereby "the rod 145 is lowered and engaged by a spring-loaded latch .149. This lowers a camming pin 150 on a bracket 150 into the path of a finger 151, articulated on bell crank 63' (FIGS. 10

' and 11), whereby this finger is deflected upwardly, on

the subsequent clockwise swing of the bell crank, and

V latches with its notch 151' onto the pin to maintain itself 39and the return of the other parts to their original beveled tip 125 at the opposite end of the lever is raised position also take place at this time.

I shall now describe the specific features of the present invention which have been outlined more generally at the beginning; Re'ference'is first made to FIGS. 4, 5, 6 and 6A;which illust-rate .rny improved system for counting only the legitimate subtractioncycles ineach digital position of the carriage 39. Square shaft 13', on which the counting wheel 13 is mounted, has rigidly fixed to it a peripherally notched coupling disk 31 adjacent a smaller disk 34, the latter being freely rotatable on a cylindrical extension of the shaft. Disk 34 has four peripheral projections 34' which form recesses between them; they, like the notches 31 of disk 31, are spaced 90 apart and thus correspond in number and relative position to the teeth of counting wheel 13.

The larger coupling disk 31 is formed with an arcuate groove 33', extending over substantially 180, engaged by a pin 33 of smaller disk 34 whereby the two disks may rotate relatively to each other over an angle corresponding to two tooth divisions of wheel 13. A coil spring 35, anchored to both disks, tends to keep them aligned in a starting position (FIG. in which the disk 34 is free to make half a turn without entraining disk 31 and wheel 13. A spring-loaded arm 32 bears upon the periphery of disk 31 to index it in any or" its four cquispaced angular positions defined by the notches 31'; a pawl 36, also spring-loaded, normally prevents clockwise rotation of disk 34 under the urging of spring 35.

A pusher member 37 is periodically operated 'by a cam 37', which plays in a generally rectangular cavity 37 of member 37, to displace the latter along a sweeping path in a clockwise motion whereby successive projections 34 of disk 34 are engaged and displaced sufiiciently to advance the disk through an angle of 90, such rotation enabling the lip 36' of pawl 36 to fall behind the next projection. The first such step, starting from the normal position shown in FIG. 5, is illustrated in FIG. 6 where the disk 31 has remained stationary while the spring 35 has been tensioned; the next step is illustrated in FIG. 6A where further stretching of the spring has occur-red. In this position the pin 33 has reached the liimit of the groove 33' so that the two disks are now positively interconnected; thus, any further rotation of the disk 34 is communicated to shaft 13' and to wheel 13 which takes one step to rotate the particular quotient pinion 5 (FIGS. 1, 3 and 16) then in mesh with it. will thus be seen that each quotient pinion takes only the correct number of steps corresponding to the number of legitimate subtractions so that the final subtraction and the subsequent compensating addition are not included in the count.

An arm 33, pivoted at 38', is adapted to disengage the lip 36 of pawl 36 from the projections 34' of disk 34 upon being swung counter-clockwise; this occurs when a the machine is not set to perform a division, and also at the end of each series of calculating cycles in any digital carriage position under the control of the back-spacing mechanism previously described. Thus, the position of FIG. 5 is restored whenever the counting wheel 13 engages a new quotient pinion 5.

FIGS. 12-15 illustrate the mechanism for accelerating the printing of the result in the case of an exact quotient with one or'rn'ore terminal zeros. A three armed lever 69 has one of its arms linked with the crank 77 via the aforementioned lever 97; another arm is pivoted-on a stud 69' which passes through a slot '70" in a stepped lever 70. The latter has two staggered shoulders 70a, 70b of which thefirst one, 70a, is normally in the path of a rod 67 which is joined to the reciproca'ble element 66 and has a hook 68 pivoted to it by a pin 68'; stud 6% also traverses a slot 67 in rod 67. A brace 152, likewise fulcrurned on stud 69, is normally urged into contact with a fixed pin 70' by a spring 153 anchored to the third arm of lever 69*. Another spring 71 biases the lever 7 0' forwardly with respect to hook 60.

When therod 66 moves rearwardly under the urging of rod 65' after the indicator 138 has released the member '72, pin 68 on rod 6'7 impinges upon shoulder 70a to displace the lever 70 from its normal position (FIG. 13) into an ineffectual intermediate position (FIG. 14)

10 in which this shoulder engages the stationary stop 70; lever 69, however, has not been moved since the slot 70" still clears the stud 69'. After the rod 67 has moved dorwardly again to withdraw the pin 68 to the right as viewed in FIGS. 13-15, spring '71 swings the lever 70 clockwise about its pivot whereby shoulder 70b is lowered into the trajectory of pin 68'. It will be noted that the lever 70 is sandwiched between the members 67 and 60 to insure its engagement with this pin.

The actuating rod 65 is also resiliently linked, via a spring 154, with an oscillatable arm 155 articulated to a member 73. Also joined to arm 155 is a rod 75 which receives a rearward thrust from rod 65, in a manner analogous to that described for rod 66, whenever the oscillation of member 73 is not blocked by the indicator in its minus position in which its upturned end 138' faces a lug '73 on that member. Thus, if the sign of the totalizer is positive in the final cycle of the sequence, i.e. if there is a finite remainder, rod 75 is displaced rearwardly to impart a counter-clockwise motion to a lever '76 to which it is hinged. The last-mentioned lever has an extremity 76 which strikes the lever 7 0 from below to lift its shoulder 70!) out of the path of pin 68 and to restore the system to the position of FIG. 13, in readiness for the next sequence of arithmetical operations. If,

however, the balance in the totalizer is zero, the movement of member 73 will remain blocked and lever 76 will not operate, hence the next rearward stroke of rod 67 will bring about the position illustrated in FIG. 15 wherein the brace 152 hooks onto the pin 70' and the lever 69 is swung clockwise. This action displaces the crank 77 to establish the end-of-division conditions previously described. At the same time a linkage 156, connecting the lefthand arm of lever 69 with a cradle 93, rocks a shaft 99 to transmit a noaddition signal to the totalizer whereupon the quotient is printed on the tape 103 with as many terminal zeros as correspond to the number of additional steps necessary to take the carriage 39 back to units position.

Let us assume, by way of example, that the machine has been set to divide 625,000 by 5. In the first digital position of the carriage, the single-digit divisor will have been aligned with the highest-ranking digit of the dividend, thus:

After the carriage 39 has taken two steps backward, upon the completion of two sequences of calculating cycles, the amount stored in the totalizer and the weighted value of the divisor will be equal, thus:

After the first cycle of subtraction, the total-izer is fully discharged; this, however, has not yet had any effect since the indicator 133 is still in plus position at the end of that cycle. The next subtractive cycle, however, produces a negative balance and with ,it a reversal of sign so that the carriage is displaced by one step and the assembly of lever 70 is brought into the position of FIG. 14. After the following additive cycle, the totalizer is again at zero and the lever 70 assumes the position of FIG. 15, with consequent termination of the division and the printing of the result as follows:

625,000 (dividend) 5 (divisor) 125,000 (quotient) (remainder) Suppose, now, that the dividend had been 625,001. The operation would then have been carried to completion, showing 1 as the remainder. The operator, however, in such case may wish to foreshorten the calculation after the first three digits of the quotient have been determined. For this purpose there is provided, as shown in FIG. 11, a lever 79 which responds toactuation of the correction key 109 and, through a crank 80, rotates a shaft 81 whereby an arm 32 thereon is swung clockwise to lift a pin 84 on a lever 83. A pin 83 at the top of that lever plays in a slotted extension 65 of an arm 85 to which a lever 157 and a hook 86, interconnected by a spring 158, are articulated. Hook 86, on being elevated by the pin 83', latches onto a lug 159' of a member tea which is controlled by the divisor key 107. The spring 158, through the intermediary of lever 157, urges upwardly the aforementioned rod 88 which is articulated to that lever and has a lug 8 8 alignable with a projection 66' on the reciprocable rod 66 (see also FIG. 11A). In its raised position, therefore, the lug 88' is effectively interposed between the rod es and the crank 77, which is pivotally connected with rod 88, even if the rod 66 is in its normal disaligned position relative to the crank. Thus, the thrust of rod 66 is now transmitted via rod '88 and crank '77 to shaft 143 whereby the normal end-of-division operations will be initiated. The result of the operation will then be indicated by the printer in the following manner:

625,001 (dividend) (divisor) 125,000 (quotient) 1 (remainder) 55,555 (dividend) 1 (divisor) 55,000 (quotient) 555 (remainder) Again, as in the preceding instances, the result is mathematically correct.

The resiliency of the linkage which actuates the arm 88 is designed to prevent jamming in the event the correction key 109 is actuated at the instant when the projection 66"overlies the lug 88'. It will also be apparent that the system controlled by lever '19 will be ineffectual if the divisor key 107 had not been operated to displace the associated member 159 since then the hook 85 would not have come to rest against the lug 15%. In this connection it may further be mentioned that the member 159, as shown in FIG/12, has connected to it a rod 160 which is linked to lever-76 and, if key 1G7 was not depressed, maintains the extremity 76 thereof raised 'so as permanently to inactivate the two-stroke assembly of FIGS. 13-15.

I claim: a

1. In a calculating machine having a movable register for the storage of a divisor, a. totalizer, automatic means for performing divisions by successively subtracting the numberof saidcyclesin any columnar position of said register, drive means for said counting means positioned to be advanced by said impulse means a predetermined number of steps for each of said cycles, resilient means tending to maintain said drive means and said counting means in an initial relative position, lost-motion coupling means interconnecting said drive means and said counting means, yieldable indexing means adapted to hold said counting means stationary during an initial displacement of said drive means by said impulse means against the force of said resilient means and to the extent permitted by said lost-motion coupling means, said coupling means being adapted to establish a positive connection between said counting means and said drive means upon a displacement of the latter by a number of steps corresponding to two of said cycles whereby said counting means is advanced a number of steps corresponding to said total number of cycles dirninishedby two, and release means controlled by said back-spacing means for disengaging said impulse means at the end of each sequence of operating cycles, thereby enabling said resilient means to restore said drive means and said counting means to said initial relative position.

2. In a calculating machine having a movable register for the storage of a divisor, a totalizer, automatic means for performing divisions by successively subtracting the divisor from a multi-digit dividend stored in a plurality of digital columns of said totalizer, back-spacing means for displacing said register column-by-co'lumn with respect to said totaliZer toward a position of alignment between the respective units digits of said dividend and said divisor, and automatic means for operating said back-spacng means at the end of a sequence of operating cycles including at least one subtractive cycle and a single additive cycle, said additive cycle occurring whenever the capacity of the totalizer is exceeded by a preceding subtractive cycle whereby the totalizer is restored to a non-negative reading of at least zero, in combination: impulse means responsive to. subtractive and additive cycles of said automatic means, counting means for determining a respective quotient digit from the total number of said cycles in any columnar position 7 of said register, drive means for said counting means positioned to be advanced one step by said impulse means I for each of said cycles, resilient means tending to maintain said drive means and said counting means in an drive rrneans by said impulse means against/the force of said resilient means and to the extent permitted by said lost-motion coupling means, said .couplingmeans being adapted to establish a positive connection between said counting means and said drive means upon a displacement of the latter by two steps whereby said counting divisor from a multi-digit dividend stored in a plurality of digital columns of said totalizer, back-spacing means for displacing said register column-by-column with respect to said totalizer toward a position of alignment between the respective units digits of said dividend and said divisor, and automatic means for operating said back-spacing means at theend of a sequence of operating cycles including at least one subtractive cycle and a single additive cycle, said additive cycle occurring whenever the capacity of the totalizer is exceeded by a preceding subtractive cycle whereby the totalizer is restored to a non-negativereading of at least zero, in combinadetermining a respective quotient digit from the total means is advanced a number of steps equal to said total number of cycles diminished by two, and release-means controlled by said back-spacing means for disengaging said impulse means from said drive means at the end of each sequence of operating cycles, thereby enabling said resilient means to restore said drive means" and said counting means to saidinitial relative position.

3. The combination according to claim 2 wherein said countingmeans comprises a profiled shaft, a toothed wheel matingly carried on said shaft and slidable thereon, a plurality of digital gears positioned alongside said shait for meshing with said toothed wheel in different axial positions of the latter, and link means interconnecting said toothed wheel and said-register for concurrent rectilinear displacement thereof by said back-spacing means whereby said toothed wheel is moved into successive engagement with said gears.

, 4. The combination according to claim 3 wherein said counting means further comprises a first disk rigid with 13 said shaft, said drive means including a second disk rotatably mounted on said shaft, said lost-motion coupling means comprising a projection on one of said disks, the other of said disks being formed with an arcuate recess receiving said projection.

5. The combination according to claim 4 wherein said first disk is provided with a plurality of equispaced peripheral notches and said second disk is provided with a like plurality of peripheral projections, the number of said peripheral notches and of said peripheral projections being equal to the number of teeth on said wheel, said indexing means comprising a spring-loaded member bearing upon the periphery of said first disk, said impulse means comprising a pusher member engageable with said peripheral projections.

6. The combination according to claim 5 wherein said pusher member is pnovided with a generally rectangular cavity, said impulse means further comprising a rotatable cam received in said cavity for imparting a sweeping motion to said pusher member.

7. The combination according to claim 3 wherein said toothed wheel is provided with a slidaible support displac'eable along said shaft, further comprising a plurality of independently rotatable gear elements respectively facing said digital gears, means including said gear elements for transferring the value of said dividend to the totalizer whereby each gear element correlated with a significant digit of the dividend is rotated from an offnormal to a normal position, a plurality of stop bars respectively linked with certain of said gear elements for displacement relatively to the path of said support, selector means operable to initiate the transfer of the dividend to the totalizer, and escapement means controlled by said selector means for shifting said register and said support to a starting position determined by the displacement of a stop bar linked with that gear element which is farthest from the gear element associated with the units digit of the dividend.

8. The combination according to claim 7 wherein all but the lowest-ranking one of said stop bars are provided with extensions adapted to entrain an adjacent stop bar associated with the next-lower digital order, said stop bars being provided with restoring means normally maintaining them in the path of said support, said extensions interconnecting all of said stop bars in cascade whereby the displacement of any higher-ranking stop bar by the gear element linked to it will similarly displace all lower-ranking stop bars out of the path of said support.

9. The combination according to claim 7, further comprising indicator means and mechanism responsive to the operation of said back-spacing means in the units position of said support for initiating a sequence of end-ofdivision steps and actuating said indicator means to register a quotient along with any remainder, said mechanism including means tfor respectively meshing said digital gears with said gear elements, means for transferring the quotient stored by said digital gears to said indicator means by restoring said digital gears to normal while in mesh with said gear elements, and means for discharging the totalizer by transferring any remainder stored therein to said indicator means.

10. The combination according to claim 9, further comprising supplemental means interposable between said back-spacing means and said mechanism for operating the latter at the end of a sequence of operating cycles in a position of said support other than said units position.

11. The combination according to claim 10 wherein said supplemental means comprises a manually controlled element whereby the calculation of the quotient can be foreshortened for registration of a partial quotient on said indicator means along with a remainder greater than the divisor.

12.. The combination according to claim 10 wherein said supplemental means comprising means responsive to a state of complete discharge of the totalizer for trans- :Eering to said indicator means a quotient with at least one terminal zero and no remainder.

13. In a calculating machine having a totalizer and indicator means for displaying quotients and remainders from division operations, in combination, transfer means for storing a dividend in said totalizer, a movable register for the storage of a divisor, calculating means for repetitively subtracting said divisor from said dividend in successive digital positions of said register until the amount stored in the totalizer in each of said positions is of a value less than that of said divisor in its corresponding decimalorder position, back-spacing means controlled by said register in response to a diminution of said amount to such value for shifting said register from a higher-ranking digital position to the position of next-lower rank, displaceable counting means coupled with said register for computing successive digits of a quotient by determining the number of subtractions in each of said positions, storage means engageable by said counting means in each of said positions for registering a respective quotient digit, end-of-division means operable by said back-spacing means in a units posit-ion of said register for transferring the stored quotient digits to said indicator means along with any remainder stored in the totalizer, and division-terminating means operable in any position of said register other than said units position for actuating said end-of-division means upon the first actuation of said back-spacing means.

14. The combination according to claim 13 wherein said division-terminating means comprises a linkage including a member controlled by the totalizer for operatively coupling said back-spacing means with said endof-division means upon the complete discharge of the totalizer whereby an exact quotient with at least one terminal zero is displayed by said indicator means upon a determination of the last significant digit of such quotient.

15. The combination according to claim 14 wherein said calculating means is adapted to perform in each digital position a final subtraction exceeding the capacity of the totalizer, whereby a negative value is read thereon, and subsequently thereto a single addition of the weigh-ted value of the divisor whereby the capacity of the totalizer is restored to at least a zero reading; said member being adapted to assume a first position in response to a positive reading of the totalizer and a second position in response to any other totalizer reading including zero; said back-spacing means including escapement means for said register, a reciprocable element coupled with said escapement means and a source of motive power periodically operative for yieldably urging said element into an oil-normal position for the actuation of said escapement means upon each operation of said calculating means, said element being positioned to be blocked by said member in said first position of the latter whereby said escapement means remains inactive; said linkage comprising an abutment in the path of said element displaceable in response to two consecutive escapement-actuating strokes of the latter.

16. The combination according to claim 15 wherein said abutment comprises a stepped lever with two shoulders, said linkage further including spring means tending to maintain said lever in a normal position against the motive force of said reciprocable element, fixed stop means for arresting said lever in an ineffectual intermediate position upon its displacement by said element bearing upon one of said shoulders, means including said spring means for aligning the other of said shoulders with said element in said intermediate position whereby a subsequent reciprocation of said element displaces said lever into an effective olt-normal position, and release means yieldably coupled with said source of motive power for periodically executing a motion tending to dislodge said lever from said intermediate position for return to said normal position by said spring means, said member being adapted to block said release means in said second position thereof. V

17. The combination according to claim 13 wherein said back-spacing means comprises a reciprocab'le element, said end-of-division means being provided With an operating member normally disaligned from the path of said element and with means controlled by said counting means in the units position of said register for relatively aligning .asid element and said operating member whereby the latter is displaced by a reciprocation of the former, said division-terminating means comprising a aligned position thereof.

t 1% element and sa-id' operating member for causing displacement of said member by said element in the dis- 18. The combination according to claim 17 wherein said division-terminating means further comprises manually operable selector means and a resilient connection between said link and said selector means.

Reierences Cited in the file of this patent UNITED STATES PATENTS 1,930,475 Gustafsson et a1. Oct. 17, 1933 2,136,694 Laiho Nov. 15, 1938 72,755,997 Ellerbeck July 24, 1956 2,834,542 S'undstrand May 13, 1958 Carnacina Sept; 22, 1959 

1. IN A CALCULATING MACHINE HAVING A MOVABLE REGISTER FOR THE STORAGE OF A DIVISOR, A TOTALIZER, AUTOMATIC MEANS FOR PERFORMING DIVISIONS BY SUCCESSIVELY SUBTRACTING THE DIVISOR FROM A MULTI-DIGIT DIVIDEND STORED IN A PLURALITY OF DIGITAL COLUMNS OF SAID TOTALIZER, BACK-SPACING MEANS FOR DISPLACING SAID REGISTER COLUMN-BY-COLUMN WITH RESPECT TO SAID TOTALIZER TOWARD A POSITION OF ALIGNMENT BETWEEN THE RESPECTIVE UNITS DIGITS OF SAID DIVIDEND AND SAID DIVISOR, AND AUTOMATIC MEANS FOR OPERATING SAID BACK-SPACING MEANS AT THE END OF A SEQUENCE OF OPERATING CYCLES INCLUDING AT LEAST ONE SUBTRACTIVE CYCLE AND A SINGLE ADDITIVE CYCLE, SAID ADDITIVE CYCLE OCCURRING WHENEVER THE CAPACITY OF THE TOTALIZER IS EXCEEDED BY A PRECEDING SUBTRACTIVE CYCLE WHEREBY THE TOTALIZER IS RESTORED TO A NON-NEGATIVE READING OF AT LEAST ZERO, IN COMBINATION; IMPULSE MEANS RESPONSIVE TO SUBTRACTIVE AND ADDITIVE CYCLES OF SAID AUTOMATIC MEANS, COUNTING MEANS FOR DETERMINING A RESPECTIVE QUOTIENT DIGIT FROM THE TOTAL NUMBER OF SAID CYCLES IN ANY COLUMNAR POSITION OF SAID REGISTER, DRIVE MEANS FOR SAID COUNTING MEANS POSITIONED TO BE ADVANCED BY SAID IMPULSE MEANS A PREDETERMINED NUMBER OF STEPS FOR EACH OF SAID CYCLES, RESILIENT MEANS TENDING TO MAINTAIN SAID DRIVE MEANS AND SAID COUNTING MEANS IN AN INITIAL RELATIVE POSITION, LOST-MOTION COUPLING MEANS INTERCONNECTING SAID DRIVE MEANS AND SAID COUNTING MEANS, YIELDABLE INDEXING MEANS ADAPTED TO HOLD SAID COUNTING MEANS STATIONARY DURING AN INITIAL DISPLACEMENT OF SAID DRIVE MEANS BY SAID IMPULSE MEANS AGAINST THE FORCE OF SAID RESILIENT MEANS AND TO THE EXTENT PERMITTED BY SAID LOST-MOTION COUPLING MEANS, SAID COUPLING MEANS BEING ADAPTED TO ESTABLISH A POSITIVE CONNECTION BETWEEN SAID COUNTING MEANS AND SAID DRIVE MEANS UPON A DISPLACEMENT OF THE LATTER BY A NUMBER OF STEPS CORRESPONDING TO TWO OF SAID CYCLES WHEREBY SAID COUNTING MEANS IS ADVANCED A NUMBER OF STEPS CORRESPONDING TO SAID TOTAL NUMBER OF CYCLES DIMINISHED BY TWO, AND RELEASE MEANS CONTROLLED BY SAID BACK-SPACING MEANS FOR DISENGAGING SAID IMPULSE MEANS AT THE END OF EACH SEQUENCE OF OPERATING CYCLES, THEREBY ENABLING SAID RESILIENT MEANS TO RESTORE SAID DRIVE MEANS AND SAID COUNTING MEANS TO SAID INITIAL RELATIVE POSITION. 